1. Field of the Invention
The present invention relates to a method of producing hearing aids to be worn in the ear and including a body member adapted to the individual shape of the inner space of the ear, which body member contains an electronic amplifier and a sound transducer.
2. Description of the Prior Art
Hearing aids which are worn in the ear are customarily adapted and shaped so that their outer dimensions conform individually to the size of the ear canal of the respective user. Until now, that result was achieved by making an impression of the space of the inner ear in order to produce therewith a mold for instance of gypsum, by means of which thereafter the plastic body member or ear shell of a plastic material can be produced as exact fitting part for a respective ear canal shape. Thereafter, the electronic amplifier and the sound transducer are mounted into this ear shell, and the spatial arrangement of these components must be selected to be adjusted to the measurements of the inner space of the ear canal.
This method of production has a variety of drawbacks because the molding of the body member and the mounting of the components must be made in a special laboratory, because the hearing aid specialist skilled in the art of hearing aids usually does not possess the necessary apparatus and the know how of molding techniques. Thus the purchaser of a hearing aid cannot obtain the hearing aid immediately from the hearing aid specialist, but rather after a prolonged waiting time. Accordingly, this production method is slow and expensive and incorporates further many possible sources of error, such that the rate of rejections when trying on the finished hearing aids is relatively high.